Installed A High Flow Cat

[bluee36e36]

i had a high flow catalytic converter on my 325is today and it makes a pinging sound from about 2000rpm up to about 3500 when the vanos kicks inn.

why does it do this? is it because i took off the resonators and will it go away if i use glasspacks as mufflers because they act as resonators?

[bluee36e36]

i didn't install it myself, i had my mechanic install it and it took about an hour and a half

[The Deuce]

More exhaust flow = Leaner mix.

If you are too lean now you could be pinging in the motor which is detonation and a VERY big deal. You need to check the a/f and make sure this isn't the case. If it is and you don't take care of it right now you coudl grenade the motor.

[tomctx]

Originally posted by bluee36e36@Mar 15 2005, 01:25 AM
i had a high flow catalytic converter on my 325is today and it makes a pinging sound from about 2000rpm up to about 3500 when the vanos kicks inn.

why does it do this? is it because i took off the resonators and will it go away if i use glasspacks as mufflers because they act as resonators?

[snapback]311650[/snapback]

What year is your 325? My 95 has two cats. Did you replace two with one? Did you replace the whole center section? Pinging is usually a sign of leaness and detonation, not a good thing.

[e30fanm3]

i doubt just installing a high flow cat would make his car run lean or else this problem would occur 10,000 times a day on here, there has to be another explaination